The MsiEnumPatches function enumerates all of the patches that have been applied to a product. The function returns the patch code GUID for each patch that has been applied to the product and returns a list of transforms from each patch that apply to the product. Note that patches may have many transforms only some of which are applicable to a particular product. The list of transforms are returned in the same format as the value of the TRANSFORMS property.

Note  pcchTransformsBuf is not set to the number of characters copied to lpTransformsBuf upon a successful return of MsiEnumPatches.

Syntax

C++UINT MsiEnumPatches(
  __in     LPCTSTR szProduct,
  __in     DWORD iPatchIndex,
  __out    LPTSTR lpPatchBuf,
  __out    LPTSTR lpTransformsBuf,
  __inout  DWORD *pcchTransformsBuf
);

Parameters

szProduct [in]

Specifies the product code of the product for which patches are to be enumerated.

iPatchIndex [in]

Specifies the index of the patch to retrieve. This parameter should be zero for the first call to the MsiEnumPatches function and then incremented for subsequent calls.

lpPatchBuf [out]

Pointer to a buffer that receives the patch's GUID. This argument is required.

lpTransformsBuf [out]

Pointer to a buffer that receives the list of transforms in the patch that are applicable to the product. This argument is required and cannot be Null.

pcchTransformsBuf [in, out]

Set to the number of characters copied to lpTransformsBuf upon an unsuccessful return of the function. Not set for a successful return. On input, this is the full size of the buffer, including a space for a terminating null character. If the buffer passed in is too small, the count returned does not include the terminating null character.

Return Value

Remarks

To enumerate patches, an application should initially call the MsiEnumPatches function with the iPatchIndex parameter set to zero. The application should then increment the iPatchIndex parameter and call MsiEnumPatches until there are no more products (until the function returns ERROR_NO_MORE_ITEMS).

If the buffer is too small to hold the requested data, MsiEnumPatches returns ERROR_MORE_DATA and pcchTransformsBuf contains the number of characters copied to lpTransformsBuf, without counting the Null character.

Requirements

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Build date: 8/13/2009